
class Circle implements ShapeArea {

    private double r;

    public Circle(double r) {
        this.r = r;
    }

    public double getArea() {
        return Math.PI * r * r;
    }

    public double getPerimeter() {
        return 2 * Math.PI * r;
    }

    public String toString() {
        return "r =" + r + ", area = " + getArea() + ", perimeter = " + getPerimeter();
    }
}
